A variety of medical diagnostic procedures involve tests on biological fluids, such as blood, urine, or saliva, and are based on a change in a physical characteristic of such a fluid or an element of the fluid, such as interstitial fluid, blood, etc.
A variety of devices have been developed for performing tests on fluids. In many such devices, fluid is introduced into the device at one location but analyzed at another. In such devices, movement of the introduced fluid from the introduction location to the measurement location is necessary. As such, these devices require a reliable way in which to move fluid from an introduction site to a measurement site easily and without adversely affecting the fluid.
A variety of different design configurations have been developed to provide for this fluid movement. One type of device relies on capillary action to move fluid through the device, where the fluid paths through the device are dimensioned to provide for this capillary action. Other designs include those intended for use with gravity, those intended for use with injection of the sample under pressure, and the like. However, moving fluid using these types of device may not be completely reliable. For example, gravity may not provide enough force to efficiently move a fluid in a flow path or flow may not be controllable.
As the interest in devices for testing an analyte continues, a need for devices that are capable of reliably moving fluid between different areas of the device remains.